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Home Topics Infectious Diseases Infections A-Z Tuberculosis (TB) General Information ›  TB - Frequently Asked Questions

TB - Frequently Asked Questions

 

What is TB?

Tuberculosis, or TB, is a disease caused by a germ (called the tubercle bacterium or Mycobacterium tuberculosis). TB usually affects the lungs, but can affect other parts of the body, such as the lymph nodes (glands), the bones and (rarely) the brain. Infection with the TB germ may not develop into TB disease.

This disease used to be common in England and Wales. For example, in the mid-1930s, over 50,000 cases of TB were notified each year. These days it is much less common. Around eight thousand people develop TB in England and Wales each year. TB is curable with a full course of treatment.

What are the symptoms?

TB disease develops slowly in the body, and it usually takes several months for symptoms to appear.

Any of the following symptoms may suggest TB:

  • Fever and night sweats
  • Persistent cough
  • Losing weight
  • Blood in your sputum (phlegm or spit) at any time

If you are concerned that you might have TB because you develop any of these symptoms, visit your family doctor for advice.

How do you catch it?

The TB germ is usually spread in the air. It is caught from another person who has TB of the lungs. The germ gets into the air when that person coughs or sneezes.

But only some people with TB in the lungs are infectious to other people. Such cases are called 'sputum smear positive' (or "open"). Even then, you need close and prolonged contact with them to be at risk of being infected. Sputum smear positive cases stop being infectious after a couple of weeks of treatment.

Mycobacterium bovis from contaminated milk was once common in the UK prior to pasteurisation of milk (older people may remember this as a route of transmission). Pasteurisation of milk removes this risk from milk.

Can anyone get it?

Anyone can get TB. But it is difficult to catch. You are most at risk if someone living in the same house as you catches the disease, or a close friend has the disease.

The following people have a greater chance of becoming ill with TB if exposed to it:

  • Those in very close contact with infectious people
  • Children
  • Elderly people
  • Diabetics
  • People on steroids
  • People on other drugs affecting the body's defence system
  • People who are HIV-positive
  • People in overcrowded, poor housing
  • People who are dependent on drugs or alcohol
  • People with chronic poor health

How is TB treated?

For many years now, we have had good treatment for TB. You have to take the treatment (usually tablets) for around six months. But it is worth it. Without treatment, many people used to die of this disease.

How important is treatment?

Treatment is vital. If you have TB disease, or if you have been infected with the germ but have not yet become unwell, you must take the treatment as directed. It is very important to complete the full course of treatment, as it will stop you being infectious, and it will remove the risk of you developing drug-resistant TB. We must not forget that TB used to kill many people before we had modern treatments.

What should I do if I think I might have TB?

Visit your family doctor for advice. He or she may then refer you to a chest clinic for some simple tests.

If you don't have a family doctor, visit your local casualty (A&E) department. They will refer you to a specialist in TB if they think you may have TB. But you should register with a family doctor as soon as possible.

What if I have been in contact with someone with TB?

Discuss this with your family doctor. Only close contacts are at risk of catching TB. You may be asked to make an appointment with your local chest clinic. Sometimes a TB nurse or chest diseases health visitor will contact you first (they will have a list of close contacts). The nurse will arrange a skin test and/or chest x-ray. This does not mean that you have TB, but it is a chance to check for any symptoms, so it is very important that you do attend, if asked.

Can TB be prevented?

Yes it can.

Most important is early detection, especially of infectious cases, and complete treatment. Early case detection reduces onward transmission of the disease and a full course of treatment is vital to prevent the disease relapsing, to prevent the development of drug-resistant strains of TB, to prevent prolonged infectiousness and preventable death. Identifying cases who have been infected through screening contacts and offering preventive treatment to reduce the risk of infected persons developing TB also contributes to preventing TB. In hospitals and institutional settings infection control measures to identify and isolate infectious cases is important. In some high-risk groups and especially among infants and young children at risk of exposure to TB, BCG vaccination can offer some protection against TB but overall, BCG vaccination plays a limited role in TB control.

What is the BCG vaccination programme?

  • The BCG immunisation increases a person's immunity to TB and protects against the most severe forms of disease such as TB meningitis.
  • The schools' programme nationally has been replaced by targeted immunisation of children at increased risk of TB.
  • The main recommendations for routine BCG vaccination of children are now: infants (aged 0 to 12 months) living in areas with a high incidence of TB (40/100,000 or greater), and any children with a parent or grandparent born in a high incidence country.
  • Local arrangements exist to opportunistically identify, test and immunise those children at increased risk of TB who will no longer be offered BCG immunisation through the schools' program.

What is the difference between TB disease and TB infection?

In most people who breathe in TB bacteria and become infected, the body is able to fight the bacteria to stop them from growing. The bacteria become inactive, but they remain alive in the body and can become active later. This is called TB infection. People with TB infection:

  • Have no symptoms
  • Don't feel sick
  • Can't spread TB to others
  • Usually have a positive skin test reaction
  • Can develop TB disease later in life

Most people who have TB infection will never develop TB disease. In these people, the TB bacteria remain inactive for a lifetime without causing disease. But in other people (for example, those who have weak immune systems), the bacteria may become active and cause TB disease.

What is extensively drug resistant TB (XDR-TB)?

Multi-drug resistant (MDR) TB describes strains of TB that are resistant to at least isoniazid and rifampicin, two of the first line drugs used in the treatment of TB. Extensively drug resistant TB (XDR-TB) refers to MDR-TB that is also resistant to any of a group of drugs called fluoroquinolones and at least one of three injectable second line anti-TB drugs (capreomycin, kanamycin or amikacin). This revised definition of XDR-TB was agreed by the World Health Organization (WHO) Global Task Force on XDR-TB in October 2006.

Further information on XDR-TB can be found on the WHO website [external link].


Last reviewed: 3 July 2013